New research to help understand the elusive male sea turtle

August 7, 2013

Researchers know all about the nesting behavior of female sea turtles, but males remain a big mystery.

There are certain questions they have about the males nearby, like which ones are fathering hatchlings and where do they go over the summer?

And a new project underway at the Sanibel Captiva Conservation Foundation will provide some of those answers.

Sea turtle mating season typically begins in March or April when the local waters are closer to 80 degrees. Months before females are seen crawling along the beach or hundreds of hatchlings are spotted rushing for the water, they need to mate.

Males nuzzle the head of a female or gently bite the back of her neck and rear flippers when mating, according to the Sea Turtle Conservancy in Gainesville, Fla. The male later attaches himself to the back of the female's shell to reproduce.

The females come ashore to lay the eggs in the same place they were born, but males never return to land and not much is known about how they contribute to the local populations. Previous SCCF research on turtle sex-ratios show that more males are produced on Sanibel than any other beach in the same latitude, because of cooler nest temperatures.

But, what happens to those males after they strike out on their own?

Amanda Bryant, a biologist with SCCF, explained that the new research was being headed up by Jake Lasala, a Ph.D. candidate from Florida Atlantic University in Boca Raton, Fla., and his advisor, Dr. Jeanette Wyneken.

They comb the beach at night for nesting Loggerhead females to tag flippers and take small samples of blood and tissue. Samples are sent back to the lab at FAU and researchers sift through the genetic material to isolate characteristics of the father.

"They can take away the genetic information from the mother and what they are left with is the genetic material of the father," said Bryant.

She said this will help answer the questions of whether the mating is done by the same group of males and how they move between populations. If researchers begin to understand the behavior of male sea turtles, she said, they can develop new ways to protect them in the wild.

It could take up to three years to collect enough data to draw accurate conclusions, she said.

Sea turtle nests produce between 75-150 hatchlings and researchers from SCCF collect 20 of them to send to the FAU lab. Hatchlings sent to the lab fare better than their siblings in the wild because they receive optimal nutrition and top water quality. After three months they are released into the ocean by the U.S. Coast Guard.

None of the work harms the sea turtles and the researchers are working under a marine turtle permit from the Florida Fish & Wildlife Commission.